Multi-segment tool and method for composite formation

ABSTRACT

A multi-segment tool and tooling system for vacuum forming a composite part. A tool can include a first tool having first and second surfaces. A second tool can have an opening positioned on a first tool in a location other than the first surface or the second surface. The first tool and second tool can receive at least a portion of a preform composite. The first tool can have a vacuum barrier attached to the first surface and to the second surface encapsulating the preform composite and the second tool. A tooling system can include a first tool having a core and a base with a core extending upwards from the base. A second tool can be positioned upon the core where the core extends above the second tool. A vacuum barrier sealed to the base and the core can include a composite, the first tool and the second tool.

FIELD OF THE INVENTION

The invention is directed to a multi-segment tool and method for vacuumforming a composite part in general, and more specifically a tool andmethod relating to composite formation of an aircraft nacelle andrelated parts.

BACKGROUND

Aircraft structures have many components that have complex shapes withmultiple curvatures. For example, various complex shapes are found inaircraft nacelle and pylon systems, thrust reversers and rocket thrusterchambers, among others. Several methods are known to form complexshapes. For thermoplastic and thermoset polymers, multiple tools can beused in injection and compression molding operations to form complexshapes. Metal forming techniques have used casting plugs to facilitatethe formation of metallic rocket thrust chambers having hour-glassconfigurations. These methods, however, are not readily adaptable forforming complex parts using vacuum bag composite techniques.

Vacuum bag forming is a method of composite fabrication that can be usedto form complex shapes using multiple tools. In vacuum bag forming, avacuum pulls a preform around the contours of a tool. Where multipletools are used to form composite parts, there must be sufficient vacuumsealing between the tools. Vacuum integrity and proper tool alignment isimportant to achieve desired end-product form and properties. Becausethe vacuum pulls a preform into every contour, seam defects result ifthere is less than precise alignment between the tools. Mechanicalfasteners such as bolts and the like have attempted to ensure alignmentamong multiple tools. Such systems, however, can be cumbersome, costlyand inadequate to minimize seam defects. In terms of vacuum integrity,gaskets, o-rings and similar devices have been used to improve vacuumintegrity between adjacent tools. These attempts often result in lessthan full vacuum integrity leading to possible product defects, poorresin cure and poor resin-to-matrix migration, contributing to potentialproduct deficiencies. In response, some have attempted to use multiplevacuum barriers to ensure vacuum integrity, but such solutions increaseprocessing complexity and cost.

A need has arisen for the ability to form multiple curvature composites,either integrally formed or formed with minimal sub-parts, where theseams are minimized, sufficient vacuum integrity is achieved andmisalignment of tools is reduced. Further, there is a need for anefficient method of forming complex shapes while providing flexibilityto accommodate changing design constraints.

BRIEF DESCRIPTION OF DRAWINGS

FIGS. 1A and 1B show a first tool of a multi-segment tool according to afirst embodiment.

FIGS. 2A, 2B and 2C show a second tool of a multi-segment tool.

FIG. 3 shows a multi-segment tool.

FIGS. 4A and 4B shows sections of the multi-segment tool taken alonglines 4-4 of FIG. 3.

FIG. 5 is a side view of a multi-segment tool with a composite placedthereon.

FIG. 6 is a side view of a multi-segment tool and composite encased inan illustrative vacuum barrier.

FIGS. 7A and 7B show removal of the second tool and composite part fromthe first tool.

FIG. 8 is a top perspective view of a second embodiment of a first toolof a multi-segment tool.

FIG. 9 is a top perspective view of a first and second tool.

FIGS. 10A and 10B show alignment features of a multi-segment tool.

FIG. 11 is a top perspective assembly view of a first and second toolwith a third tool being added.

FIG. 12A is an exploded perspective view of a portion of the bottom ofthe third tool.

FIG. 12B is an exploded perspective view of a portion of the first tooland of the third tool.

FIG. 13 shows a multi-segment tool on a frame.

FIG. 14 is a cut away close-up of a multi-segment tool with one fairingremoved.

FIG. 15 shows a multi-segment tool with a composite and illustrativevacuum barrier

FIG. 16 shows a perspective assembly schematic of a multi-segment tooland composite.

SUMMARY

A multi-segment tool for vacuum forming a composite part can include afirst tool having a first surface and a second surface. A second toolcan have an opening. The second tool can be capable of receiving thefirst tool through the opening. A second tool can be further capable ofbeing positioned on the first tool in a location other than the firstsurface or second surface. The first tool can receive at least a portionof a preform composite. The second tool can receive at least a portionof the preform composite. The first tool can have a vacuum barrierattached to the first surface and to the second surface, wherein avacuum barrier encapsulates the preform composite and the second tool.

A tooling system for vacuum forming a composite part can include a firsttool having a core and a base with the core extending upwards from thebase. A second tool can be positioned upon the core in such a way that aportion of the core extends above the second tool. The tooling systemcan further include a composite formed on the first tool and the secondtool, the composite having a complex shape. A vacuum barrier can bepressure sealed to the base and to the portion of the core that extendsabove the second tool. The vacuum barrier can be capable of forming apressure seal that includes the composite, the first tool and the secondtool.

A method of forming a composite part can include providing a first tooland positioning a second tool on a first tool. The second tool can havean opening capable of receiving the first tool through the opening. Amethod can include applying a composite preform on at least a portion ofthe second tool. A method can include vacuum sealing the compositepreform by securing a vacuum barrier to the first tool while the preformand second tool can be encapsulated within a vacuum barrier. A methodcan further include curing the preform to form a composite part.

The foregoing and other features, aspects and advantages of theinvention will be apparent from a reading of the following detaileddescription together with the accompanying drawings, which are describedbelow.

DESCRIPTION

Certain exemplary embodiments of the present invention are describedbelow and illustrated in the accompanying Figures. The embodimentsdescribed are only for purposes of illustrating embodiments of thepresent invention and should not be interpreted as limiting the scope ofthe invention. Other embodiments of the invention, and certainmodifications and improvements of the described embodiments, will occurto those of skill in the art, and all such alternate embodiments,modifications and improvements are within the scope of the presentinvention.

The tool and method in general comprises two or more tools that can matewith one another to form a desired mold profile. Composite materials arethen applied upon or laid up on the tools. The composite can be thenencased within a vacuum barrier or bag, which can be sealed around thecomposite and secured to surfaces of one of the tools. After curing, theparts can be selectively removed, resulting in a composite structurehaving a complex shape. In a preferred embodiment, a 360 degree complexshape can be produced for use as, for example, a one-piece inner barrelof an aircraft engine nacelle.

More specifically, a first embodiment for a tool or system for vacuumforming a composite part is shown in FIGS. 1 through 7. FIG. 1A shows afirst tool 30. First tool 30 can have a top portion 32 and a bottomportion 36. Top portion 32 has a top edge 34, and bottom portion 36 hasa bottom edge 38. In the embodiment shown, both top edge 34 and bottomedge 38 are circular and form planes that are substantially in parallelorientation with one another. First tool 30 can be a 360 degree tool asshown. A 360 degree tool refers to a tool that can be used to mold3-dimensional parts that have some type of void or internal open cavitytherewithin. Such parts in a preferred embodiment are formed partiallyor completely around the tool, thereby creating a partial or extendedannular opening in the part. For example, 360 degree tools can be usedin the aircraft industry to produce nacelles, pylon systems, thrustreversers, rocket thruster chambers, etc. In a preferred embodiment, the360 degree tool has an uppermost portion that has a smaller crosssectional area than portions elsewhere on the tool, thereby permittingthe part to be removed upwardly along an axis substantially aligned withthe annular opening formed by the tool. Thus, a 360 degree tool can befrusto-cone or frusto-pyramid to facilitate creation of such annualparts.

First tool 30 can have outer shape profiles designed as necessary toconform to the desired composite part and/or to mate with additionaltools. Bottom portion 36 can have bottom side 37 that extends upward andinwardly from bottom edge 38. Similarly, top portion 32 can have analignment bevel 33 that also slopes upward and inwardly towards top edge34. Alignment bevel 33 can also facilitate tool alignment. To facilitateremoval of tool(s) and/or composite part(s), alignment bevel 33 andbottom side 37 preferably have right (90°) or acute (less than 90°)angles θ₁, θ₂, respectively, (as shown in FIG. 1A) measured with respectto a line 31 orthogonal to a plane defined by bottom edge 38.

First tool 30 has an alignment ridge 35 as shown, for example, in FIGS.1A and 1B. Alignment ridge 35 in this embodiment can be a lip, machinedstep, indentation or projection on the first tool 30. More than onealignment ridge 35 can be present on first tool 30, to facilitatepositioning the first tool 30 with a mating tool having a complexprofile, or with additional tools. Alignment ridge 35 is formedcircumferentially around first tool 30, and in parallel configuration tothe plane formed by bottom edge 38. In alternate embodiments, alignmentridge 35 can form any angle with respect to the plane formed by bottomedge 38. Also, alignment ridge 35 can be any shape as determined by theneeds of mating alignment of additional tools. A clocking pin (notshown) can be located on alignment ridge 35 to facilitate the locationand alignment of additional tools.

FIG. 1B is a top view of first tool 30, showing the bottom edge 38,bottom side 37, alignment ridge 35, alignment bevel 33 and top edge 34.Interior space 39 facilitates cooling and access to mechanical andvacuum components.

FIGS. 2A, 2B and 2C show an embodiment of a second tool 40, which iscapable of mating alignment with first tool 30. Second tool 40 has a top42, bottom 44 and a second tool side 48 extending therebetween.

FIG. 2B shows a cross section, taken along lines 2B-2B of FIG. 2A. Top42, bottom 44 and second tool side 48 are shown. Side 48 has a thicknessT₁ at the top and a thickness T₂ at the bottom. Side interior wall 47can be configured to fit atop the first tool 30 and be positionedadjacent to alignment bevel 33. To accomplish this, wall 47 can beoriented at angle θ₂ to sit flush against alignment bevel 33, which isthe same angle θ₂ orientation of the alignment bevel 33 of the firsttool top portion 32 (see FIG. 1A). Interior edge 43 located at the top42 of second tool 40 defines an opening, or an interior cross-sectionalarea 45, as shown in FIG. 2C.

FIG. 2C is a top view of second tool 40 shown in FIG. 2A, showing thecross-sectional area 45 defined by the interior edge 43, and the topthickness T₁. This interior cross-sectional area 45 allows the secondtool 40 to fit over the top portion 32 of the first tool 30.

As shown in FIGS. 2A and 2B, an outer wall 49 of side 48 of the secondtool 40 generally extends outwards from the bottom 44, in an invertedfrusto-cone shape. Other examples of a shape of a second tool include aninverted frusto pyramid, where the top perimeter also is larger than thebottom perimeter. The second tool 40 can be integrally formed, such asshown in FIGS. 2A, 2B and 2C, or can comprise several discrete segments(not shown) disposed radially or circumferentially to form a 360 degreepart.

As shown in FIGS. 3, 4A and 4B, the second tool 40 can be lowered ontoand placed atop first tool 30. When the first tool 30 and second tool 40are assembled, a multi-segment tool 10 is formed. Multi-segment tool 10has an outer shape 12 that will become the form on which a composite islaid, as discussed below. The embodiments shown reflect a configurationwhereby top edge 34 of first tool 30 extends above the top 42 of secondtool 40.

FIG. 4A is a cross-section taken along lines 4-4 of FIG. 3. Second tool40 is shown placed upon the top portion 32 of the first tool 30. FIG. 4Bis an exploded view of the circled area shown in FIG. 4A, and shows theinterior wall 47 of second tool 40 adjacent to the alignment bevel 33 ofthe first tool 30. The bottom 44, having a thickness T₂, of side 48 ofthe second tool 40 is positioned atop the alignment ridge 35 of thefirst tool 30. The second tool 40 meets the alignment ridge 35 at joint15.

First and second tools 30, 40 can be formed from a variety ofnon-metallic materials such as composites or metallic alloys such as,for example, aluminum, nickel, iron, steel or a substantiallyinexpansible alloy, such as Invar® nickel steel alloy, as needed.Selection of a tool material typically is based on forming method,composite part tolerances, number of curing and/or heating cycles,coefficient of thermal expansion of the tooling material, desired orrequired surface condition of the composite part, compositeconstituents, and cost, as is generally known in the art. In a preferredembodiment, the tools are formed of Invar® alloy.

FIGS. 5 through 7B show the addition of a composite part 16 tomulti-segment tool 10. In FIG. 5, composite part 16 can be laid upon themulti-segment tool 10 by known methods, including for example, layingtogether individual plies of a pre-impregnated composite to create thefinal laminated structure. In a preferred embodiment, the composite isprepared by hand lay up of pre-impregnated plies of a graphite fabric.The composite part 16 can be a complex shape due to the geometries ofthe first part 30 and second part 40.

The composite part 16, which sometimes is called a preform prior tocuring, is typically comprised of a reinforcement and a matrix.Reinforcements can be carbon, aramid fibers, para-aramid fibers, glassfibers, silicon carbide fibers, high strength polyethylene or othercomposite fiber materials as known in the art. The reinforcementmaterial can be short or long fibers, woven, laid-up reinforcements,laminates or any combination thereof. The matrix can be a thermoset orthermoplastic polymeric resin such as polyester, vinyl ester, epoxy,phenolic, polyimide, polyamide, polypropylene, PEEK or baselimide. In apreferred embodiment, the reinforcement is graphite and the matrix isepoxy.

FIG. 6 illustrates the addition of a vacuum barrier 20 that encases thecomposite part 16 and portions of the multi-segment tool 10. Vacuumbarrier 20 can be secured and sealed to bottom portion 36 and topportion 32 of first tool 30, using securing methods known to those ofskill in the art. In a preferred embodiment, the vacuum barrier 20 issealed by a sealant tape. Sealed in this manner, the vacuum barrier 20encases the composite part 16 and the second tool 40.

Vacuum barrier 20 can be a flexible polymeric material, or othermaterial as is known in the art, sufficient to withstand temperaturesand pressures encountered with vacuum bag composite curing. A vacuum isdrawn from the space between vacuum barrier 20 and multi-segment tool 10using a vacuum source (not shown) such as a compressor or venturi pumpas is known in the art. Pressure approaching approximately oneatmosphere forces composite part 16 against the outer profile 12 ofmulti-segment tool 10.

After securing the vacuum barrier 20 and achieving the desired pressureconditions, the composite part 16 is then cured. Cure, or curing, asused herein, refers to the process that results in cross-linking orsolidification of a matrix and reinforcement. Curing can occur inpressurized vessels at elevated temperatures in devices such as anautoclave, as is known in the art. In an alternate embodiment, curingcan occur at ambient temperature and/or atmospheric pressures. Multiplecures cycles can be used as the need may arise. For example, a preformcan undergo a first and second cure to form composite part 16. In oneexample using the tool described herein, a woven carbon fiber-epoxycomposite part 16 was exposed to about 350° F. simultaneously withpressures ranging between about 35 psi to about 100 psi, preferably fromabout 70 to 80 psi, for about 120 minutes inside an autoclave. Theparticular temperature-pressure-time variable can be adjusted accordingto the particular reinforcement and matrix combination used in thepreform, as is known in the art.

FIGS. 7A and 7B show disassembly following cure and removal of vacuumbarrier 20. The second tool 40 can be first lifted or axially removedfrom the first tool 30 as shown in FIG. 7A. As shown in FIG. 7B,composite part 16, having a complex shape, can then be removed axiallyfrom the first tool 30.

A second embodiment of a tool or system for forming a composite part isshown in FIGS. 8 through 16.

Referring to FIG. 8, first tool 130 comprises a core 131 shown sittingatop a base 139. Core 131 comprises top portion 132 and middle portion136. A ridge 135 is located between the top portion 132 and middleportion 136. Core 131 can be positioned off-center of first tool base139 as shown. Such an off-center placement allows for support for anon-concentric second tool 140. In alternate embodiments, core 131 canbe centered on first tool base 139 to support concentric second andthird tools 140 and 160. Alignment guides 154 can be located on themiddle portion 136 of the core 131. Guides 154 can be locatedintermittently in relation to each other around middle portion 136.Preferably four (4) guides are used, and are parallel to one another andpositioned circumferentially around the middle portion 136. Although thetop portion 132 of first tool 130 can be a cylinder as shown, topportion 132 can also slope inwards in a truncated conical shape (notshown). The open inner volume 170 of first tool 130 helps provide aircirculation and minimize tool heat-up during subsequent curing. The base139 has a top surface 151.

FIG. 9 shows the addition of a second tool 140 and a transport frame118. Second tool 140 can be positioned atop top surface 151 (not shownin FIG. 9) of first tool 130. As shown also in FIG. 10A, recess 157 onthe interior side of the second tool 140 can cooperate with guides 154to facilitate positioning and alignment of the second tool 140 overfirst tool 130. So positioned, supporting core 131 extends up throughthe second tool 140 leaving guides 154 partially exposed and ready toreceive additional tools. Transport frame 118 can support and transportthe assembled multi-segment tool as needed. Transport frame 118 can besteel or other metallic alloys.

Second tool 140 has a top edge 142 and bottom edge 144. Bottom edge 144is generally circular and planar. As shown, top edge 142 also is showngenerally non-parallel to the plane formed by bottom edge 144. The useof such a non-parallel interface, also called a spline form split line,can assist in removal of the composite from the tool following curing.In practice, various non-parallel interfaces can be used, but preferablythe angle between the interfaces will be greater than about fivedegrees. Bottom profile 145 defines the surface to which a preform willlater be partially applied, as discussed below.

FIGS. 10A and 10B show details relating to a guide 154 and recess 157.Tongue 153 of guide 154 fits within recess 157 of the second tool 140and assists in guiding and aligning the second tool 140 on to first tool130. Notches 155 permit clearance for members 166 (shown in FIGS. 12B)of third tool through ridge 135. A first index shoe 152, as shown inFIG. 10B, is located on the interior of the second tool 140 andfacilitates alignment by receiving a second index shoe 156 of third tool160 (shown on housing 163 in FIG. 12A). First and second index shoes 152and 156 can help the second and third tools 140 and 160 form a smoothjoint therebetween and limit deviation between the two tools. In apreferred embodiment, index shoe 152 has a recess into which projectionfrom index show 156 fits.

FIG. 11 shows the addition of a third tool 160, ready to be lowered andpositioned upon first tool 130 and into contact with the second tool 140to form a multi-segment tool. Third tool 160 comprises a station datumplane 168, housing 163 and upper profile 165. The station datum plane168 allows for the planar reference for coordination and fit between thetools. Station datum plane 168 can also allow for the verification ofcompliance with the desired contour tolerances. Station datum plane 168also can provide support for fairings 126 (as shown in FIG. 13). Abottom edge 164 of upper profile 165 cooperates and mates with top edge142 and lower profile 145 of second tool 140. An inner opening 167 ofthird tool 160 receives first tool 130. The housing 163 can have aninterior lip (not shown) that cooperates and rests upon ridge 135. Atthe bottom of the housing 163, feet 169 (also shown in FIG. 12A) allowthe tool to be placed on a hard surface without damage to the tool whennot in use.

FIGS. 12A and 12B show hardware useful for aligning first, second andthird tools 130, 140, and 160. A second index shoe 156 can be positionedon housing 163. When installed, the second index shoe 156 is alignedwith the first index shoe 152 on second tool 140 (as shown in FIG. 10B).As discussed above, the index shoes can axially engage through a tongueand groove or other suitable mechanical, electronic or magnetic linkage.Preferably, four pairs of index shoe pairs are located circumferentiallyon the third and second tools 160 and 140. The guides 154 (shown in FIG.12B) of first tool 130 cooperate with alignment members 166 located onhousing 163 of third tool 160. Alignment members 166 can provide a closetolerance radial index with guides 154 as shown in FIG. 12B. Thus,alignment members 166 can align and index first tool 130 and third tool160. Index shoes 152 and 156 can align and index second tool 140 andthird tool 160.

FIG. 13 shows an assembled multi-segment tool 110 also having fairings126. Preferably four (4) fairings 126 can be positioned on top of thirdtool 160 and around the top portion 132 of the first tool 130. Thefairings 126 can be formed from a lightweight fiberglass material. Othercomposites, metals and cured plastics capable of withstanding elevatedtemperatures can also be used. For example, light weight metallicalloys, such as aluminum and the like, can form fairings 126. Fairings126 cover mechanical fasteners and lifting hardware or other highprofile gaps on the station datum plane 168 (as shown in FIG. 11) andhelp prevent bag pinch around sharp objects present on the top of thirdtool 160. Casters 182 attached to the transport frame 118 aid inmovement of the multi-segment tool.

In the assembled condition, multi-segment tool 110 comprises first tool130, second tool 140 and third tool 160, assembled together. Lowerprofile 145 is mated to upper profile 165, and together form a surfaceto which a composite preform can be placed.

FIG. 14 shows an exploded and partially disassembled view of the thirdtool 160, station datum plane 168 and fairings 126. Various mechanicalfasteners and lifting hardware 169 on third tool 160 facilitatetransport and positioning of third tool 160 around the top portion 132of the first tool 130 and onto second tool 140. As shown, the topportion 132 extends above the third tool 160, and provides a surface towhich a vacuum bag can be attached as discussed below.

FIG. 15 shows the multi-segment tool 110 after a composite part 216 anda vacuum barrier 220 has been applied thereto. The composite part can beintegrally formed in 360° or in portions thereof. As stated above, thecomposite may be laid upon the tool 110 by known methods, including forexample laying together individual plies of pre-impregnated composite tocreate the final laminated structure. The composite part 216 can be acomplex shape due to the geometries of the multi-segment tool 110. Thecomposite can be comprised of a reinforcement and a matrix, such asdescribed with the first embodiment above. The segment of the topportion 132 that extends above the fairings 126 serves as an uppersealing surface 137 for the vacuum barrier 220. The outer surface of thebase 139 serves as a lower sealing surface 133 for the vacuum barrier220. The vacuum barrier 220 extends over composite 216 and first, secondand third tools (not shown in FIG. 15). Vacuum barrier 220 is secured toupper sealing surface 137 and lower sealing surface 133 using securingmethods known to those in the art. In a preferred embodiment, the vacuumbarrier 220 is sealed by a breather cloth and bagging putty (not shown),as is known in the art. Further processing can occur to cure thecomposite part 216 in the similar manner as discussed in relation to thefirst embodiment above.

FIG. 16 is a schematic view, illustrating how the components of themulti-segment tool 110 and composite 216 are disassembled followingcuring. Initially vacuum barrier 220 (not shown in FIG. 16), twoportions 132 and fairings 126 can be removed from multi-segment tool110. Thereafter, third tool 160 can be axially removed frommulti-segment tool 110. Axial removal of third tool 160 initially leavescomposite part 216 around second tool 140. Composite part 216 can thenbe removed from first and second tools 130 and 140. Subsequent steps caninclude removal of the second tool 140 for storage and/or cleaning.Following disassembly, first 130, second 140, third 160 tools, andfairings 126 can be used to reconstruct multi-segment tool 110 forsubsequent composite part formation.

This invention permits more than one removable piece of tooling to beused in conjunction with other tools, without the requirement of vacuumsealing surfaces between the tools. A vacuum barrier can be sealed to asingle structure, and capture any intermediate tools along with thepreform or composite. This eliminates the need to have sealing surfacesbetween removable tools, thereby minimizing leak exposure and the numberof resulting seams. This method is advantageous for 360 degree toolingapplications, but also can be used in other non-360 degree applications.Since intervening pressure seals are not required, the interfacesbetween upper and lower parts can be made with greater mechanicaltolerances.

In addition, the use of a minimal components ensures proper alignment asdescribed above, which often is a problem with multi-segmented bondtooling. The use of indexes helps ensure accurate mating or clocking oftool sections and profiles.

Embodiments of this invention provide many advantages over prior artmethods. Since the vacuum barrier is attached to portions (e.g., top andbottom as shown in embodiments) of a first tool that is itselfvacuum-tight, the lower profile (e.g., element 145) and upper profile(e.g., element 165) of the embodiments that receive the preform need notbe vacuum-tight. Hence the lower profile and upper profile (whencombined, sometimes called in the art a “facesheet”) can accommodatetool holes, through bushings, and other discontinuities that often areneeded for mechanical assembly, tool replacement and cleaning. Hence,the facesheet can have greater tolerances for machined parts, andbroader standards for welding around holes and projections thatotherwise would increase tool manufacturing complexity. Such tolerances,through holes and other often minor incongruities in the facesheet havelimited negative impact on vacuum integrity. This advantage simplifiesoverall tool construction and allows for more efficient tool turnaroundand cleaning following use.

The above descriptions of various embodiments of the invention areintended to describe and illustrate various elements and aspects of theinvention. Persons of ordinary skill in the art will recognize thatcertain changes and modifications can be made to the describedembodiments without departing from the scope of the invention. All suchchanges and modifications are intended to be within the scope of theappended claims.

1. A multi-segment tool for vacuum forming a composite part comprising:a first tool having a first surface and a second surface; a second toolhaving an opening, the second tool capable of receiving the first toolthrough the opening and further capable of being positioned on the firsttool in a location other than the first surface or second surface; thefirst tool being capable of receiving at least a portion of a preformcomposite; the second tool being capable of receiving at least a portionof the preform composite; the first tool further being capable of havinga vacuum barrier attached to the first surface and to the secondsurface, while the vacuum barrier encapsulates the preform composite andthe second tool.
 2. The multi-segment tool of claim 1 where the firsttool is uninterrupted and without seams that require sealing duringencapsulation by the vacuum barrier between the first surface and thesecond surface.
 3. The multi-segment tool of claim 1 whereby the firsttool is a circumferential 360 degree tool.
 4. The multi-segment tool ofclaim 1 whereby the second tool is a circumferential 360 degree toolhaving an opening.
 5. The multi-segment tool of claim 3 where the firsttool has a projecting element that comprises the second surface, theprojecting element protrudes through the opening of the second toolpermitting the second surface to be capable of sealing engagement withthe vacuum barrier.
 6. The multi-segment tool of claim 1, furthercomprising a third tool positioned on the first tool in such a manner topermit the vacuum barrier to be capable of holding a vacuum seal whileencasing the preform, the second tool and the third tool.
 7. Themulti-segment tool of claim 1, further comprising an alignment means topermit alignment of the first tool and second tool when positioned. 8.The multi-segment tool of claim 7, where the alignment means comprises aridge located on the first tool, capable of contacting at least aportion of the second tool to assist in alignment.
 9. The multi-segmenttool of claim 7, where the alignment means comprises one or more indexshoes on the first tool and on the second tool to assist in alignment.10. The multi-segment tool of claim 1, wherein: the first tool has acore and a base, the core extending upwards from the base, and the basehaving a first plane; the second tool is positioned upon the core insuch a way that a portion of the core extends above the second tool; andthe second tool and the first tool are mated together at a second plane.11. The multi-segment tool of claim 10, wherein the first plane isparallel to the second plane.
 12. The multi-segment tool of claim 10,wherein the first plane is at an angle greater than about five degreesto the second plane.
 13. The multi-segment tool of claim 10, furthercomprising a third tool that mates with the second tool and defines athird plane.
 14. The multi-segment tool of claim 13, where the thirdplane is parallel to the second plane.
 15. The multi-segment tool ofclaim 13, wherein the third plane is at an angle greater than about fivedegrees to the second plane.
 16. A multi-segment tool for vacuum forminga composite part comprising: a first tool having a first surface and asecond surface; a second tool having an opening, the second tool capableof receiving the first tool through the opening and further capable ofbeing positioned on the first tool; the first tool and the second tooltogether forming an outer shape when the first tool and second tool areassembled, the outer shape including at least a first tool outer surfaceand at least a second tool outer surface, both outer surfaces beingcapable of receiving a perform composite; the first tool further beingcapable of having a vacuum barrier attached to the first surface and tothe second surface, while the vacuum barrier encapsulates the preformcomposite and the second tool.